Stair climber



FIG. 1 is a perspective view of a stair climber showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is another perspective view thereof.

The broken lines in the drawings of the stair climber form no part of the claimed design. 

CLAIM The ornamental design for a stair climber, as shown and described. 